This is the latest salvo is the fast food breakfast wars. Burger King competitor McDonald's(MCD) does not have hamburgers on its breakfast menu, but the company has considered expanding its breakfast menu hours to try and correct a slump in sales. McDonald's also wooed customers during breakfast hours last month with free coffee for two weeks.

KFC 'doubles down' on China

Taco Bell starting serving breakfast in March and introduced the Waffle Taco, a breakfast sandwich wrapped inside a waffle with syrup.